Fish fingerlings
Dan Gruendemann, Black Creek, held a walleye/sauger crossbred fingerling that is part of a U.S. Department of Agriculture study testing the feasibility of getting the hybrid from egg to market in one year. Photo credit: Sara Bredesen

Scaling Up: Fish Study Looking Good for Commercial Production

Posted: Wednesday, September 12, 2012 6:49 am

By Sara Bredesen | Regional Editor | The Country Today

BLACK CREEK — Dan Gruendemann has been building toward a serious business in commercial stocking and food fish for about 12 years. He is really excited about early results of growth trials being held on his farm south of Black Creek in Outagamie County.

If the federally funded trials pan out the way he thinks they will, his Northside Enterprises will be one of the Wisconsin aquaculture businesses ready to take advantage of new technologies.

Gruendemann, working in conjunction with the UW-Stevens Point Northern Aquaculture Demonstration Facility, hopes to show that early-spawned purebred walleye — about two months earlier than normal — can be commercially raised in pond conditions on commercial feed from start to finish. That would give growers a larger fish going into their ponds in the spring and larger fish to sell in the fall when they either go into lakes as stockers or to processors as fillets.

A second part of the study hopes to show that early-spawned hybrid walleyes (sauger x purebred walleye) can be grown in indoor systems up to market size in one season.

The research is being conducted as Phase I under a nearly $100,000 U.S. Department of Agriculture Small Business Innovation Research grant. Phase II, if approved, will move the study from the feasibility level to commercial production.

Gruendemann, who is chairman of the board of the Wisconsin Aquaculture Association, said the crossbreds — known as saugeyes — are found naturally in Wisconsin waters and are as good to eat as a purebred walleye or a perch. In the food market, walleyes sell for a little less per pound than perch, but the margin is made up in the size of the fillets.

“I took an interest in it, because you can raise these fish to a pound to a pound and a half in a single growing season, where the perch you’re going to get three to the pound on an indoor system,” Gruendemann said.

Initial work on early spawning and raising on commercial feeds started at Iowa State University about 15 years ago. Wisconsin researchers at NADF picked it up about three years ago and got a good handle on early-life-stage feeding, Gruendemann said. Hatchlings for the study are being provided by NADF to Gruendemann at his business, Northside Enterprises.

Northside includes a small indoor recirculation system where Gruendemann has 3,000 purebred and 3,000 saugeyes under identical climates, identical ages and identical loading levels. Fish are weighed and measured every three to four weeks to compare growth rates.

Grant funding was not available early enough this year to have early-spawned fish in the system, but having information on this year’s later spawning stock will offer much more data for comparison, Gruendemann said. In effect, the one-year study is being conducted over two seasons worth of fish. New early-spawned babies will go into the system next February or March. Some will be moved to outside ponds when temperatures moderate.

“For the pond study, we’ll be doing hybrid and doing purebreds, and there’ll be four ponds — possibly six — with 1,000 in each pond, so we’ll get some really good replicates and try to control identical conditions outdoors,” he said.

Gruendemann said it is huge for Wisconsin’s commercial fish growers to be able to turn fish around in one year and not have to winter them over.

“To get these fish up to a market size in one year is the goal, so you’re not tying up your ponds for two years for one crop,” he said.

Indoor growers are just as eager not to tie up their systems.

“Typically, what we’ve seen with these fish is that you can harvest the hybrids by Christmas for a smaller fillet. It’s still going to be larger than a perch fillet at Christmastime,” Gruendemann said. “A 10- to 11-inch walleye.”

Compacting the growing season also is huge for Gruendemann, who is working with his wife, Kim, and father, David, on the fish business. He said it has taken a lot of years to get to the point where they are ready to go seriously into business, and several grocery chains are already angling for all the fish they can produce.

The Gruendemanns broke ground Sept. 5 on a 12,000-square-foot building for a commercial-scale indoor recirculation system that will have capacity for 25 to 30 tons of fish annually. A processing facility is built but awaiting equipment, and a farmgate store is in the works. They have a variety of fish already in their ponds, including yellow perch, brook trout and bluegills.

“We believe you have to go cradle to grave; cut out as many middlemen as you can, so we hatch our own eggs on some of these species, and we raise our own fish, and we want to be able to process them and sell them,” he said. “I believe it’s the way to become profitable, but it’s not cheap.”

Gruendemann said several other business ideas are on hold until the grant study is finished.

“This will get published with our results so that everybody can see what we did and decide on their own; does that look like a profitable business for us to get into or not; did it work or did it not work?” Gruendemann said. “From what we’re seeing, it’s looking positive.”